The lungs is your answer :)
Answer:
Metabolic wastes or excretements are substances left over from metabolic processes (such as cellular respiration) which cannot be used by the organism (they are surplus or toxic), and must therefore be excreted.
This is what i found out i hope this is a good enough answer!! :P
I am pretty sure it would be Swimming Laps
The answer is A stress can lead to increased vulnerability to infections and immune deficiency disorders
Bone, which is made of collagen, which is strenghtened by calcium phosphate
